Universal-joint coupling for drilling-machines.



J. P. KARNS;

UNIVERSAL JOINT GOUPLING FOR DRILLING MACHINES.

APPLIUATION FILED APR. 8,

Patented June 25, 1912.

JOHN PRUE KARNS, OF BOULDER, COLORADO.

UNIVERSAL-JOINT COUPLING FOR DRILLING MACHINES.

Specification of Letters Patent. 1

Patented June 25, 1912.

' Original application filed May 25, 1909, Serial No. 498,246. Divided. and this application filed April 8,

' 1910. Serial No. 554,224.

To all whom if; may concern Be it known that I, JOHN P. KARNs, a citizen of the United States, residing at Boulder, in the county of Boulder and State of Colorado, have invented a new and useful Universal-Joint Coupling for Drilling- Machines, of which the following is a specification.

This invention has reference to improvements in drilling machines and especially to a means for coupling the prime mover to the drill shaft of a drilling machine so that want of alinement between the shaft of the drilling machine carrying the drilling head and the shaft of the prime mover will not in any wise interfere with'the proper operation of the structure.

The present application is a division of another application filed by me on May 25, 1909, under Serial Number 498,246 for improvements in drilling machines. In the said original application there is illustrated a drilling machine of massive proportions wherein there is provided a drill head of a diameter equal to the diameter of the tunnel to be formed and this drill head carries cutting tools or chisels in fixed relation to the drill head and designed to attack the breast of the tunnel being drilled, simultaneously, the action of the chisels being due to impact blows delivered by the chisels on the head or breast of the tunnel by a forward movement ofthe drill head and shaft carrying the same, the weight and momentum of the drill head and shaft causing the action of the cutting tools upon the surface attacked. The ponderous nature of the ma chine presents problems not found in like machines use for'drilling small holes and it is for one of these problems that the-pres ent invention is designed to provide.

The invention will be best understood from a consideration of the following detail description taken in connection with the accompanying drawing forming a part of this specification, in which drawings:

Figure 1 is an elevation of a drilling machine'in connection with which the present invention is to be used, a portion of the machine being shown in section. Fig. 2 is an end elevation of the casing for the coupling structure, the power shaft being shown in cross section. Fig. 3 is a section on the line A-B of Fig. 2. Figs. 4:, 5, and 6 are detail views of the adjacent portions of the power shaft and drill head shaft at the point of junction of the two.

Referring to the drawings, there is shown a drill head 1 mounted at one end of ashaft 2 which in turn is supported by suitable journal bearings 3 and 4 in spaced relation .one to the other, while intermediate of these bearings there is provided a feeding structure 5 for imparting to the shaft 2 during its reciprocatory movement, a slow rotative movement so that the cutters of the drill head 1 will attack all points of the breast of the tunnel being formed.

The construction of the parts so far referred to is fully set forth in the aforesaid application of which the present application is a division, and as these parts form no part of the present invention, specific description thereof is omitted.

In the operation of the drilling machine the drill head is moved back and forth by means of power applied to the shaft 2 at of the shaft.

The end of the shaft 2 extending through the journal bearings L is, inthe particular structure shown in'the drawings, enlarged in diameter and'to the rear ofthis point the shaft is reduced in diameter as indicated at 6. Surrounding the reduced portion6 of the shaft 2 is a sleeve 7 extending from the said enlargement of the shaft to a point beyond the rear end of the rear extension 6 of the shaft and is there inturned to form a circular ledge 8, the inner edge of which forms the walls, of an axial passage 9, through which extends a connecting member 10 in the form of a bar or shaft coming from a suitable actuating mechanism capable of imparting reciprocating motion to the said bar or shaft but which forms no part of the present invention and is therefore not shown in the drawing. An electric, compressed air, or other suitable engine may be used for this purpose.

The rear end of the extension 6 of the shaft 2 is formed with an approximately semispherical recess 11, the axis of curvature of the recess being a short distance beyond the end of the extension 6 in the longitudinal axis of the shaft, in the particular showing of the drawing. Seated in the recess 11 is a substantially semispherical block 12, preferably though not necessarily of bronze and this block is shown as provided with a frustO-conical extension 13, the said block 12 constituting a bearing ball having a seat in the semispherical recess 11.

The end of the rod or shaft 10 within the sleeve 7 is enlarged into a cylindrical head 1 1 terminating in a plane face 15. The curved face of the block 12 where engaging the recess 11 is provided with lubricant directing grooves 16 and the plane face 15 of the head 14 is provided with a lubricant directing groove 17. The inner wall of the inwardly directed flange 8 is formed with a curved seat 18 of generally annular form surrounding the passage 9, the curvature of this seat being from the same center as the curvature of the ball 12.

Lodged in the seat 18 is a ring 19 having one wall conforming to the seat 18 and the 7 other wall plane and bearing against the face of the head 14 remote from the face 15, the said face of the head 14: where engaged by the ring 19 being also plane and parallel with the face 15. The ring 19 where engaging the seat 18 is provided with lubricant directing grooves 20 and the portion of the head 14 engaging the ring 19 is provided with lubricant directing grooves 21.

Extending through the portion 6 of the shaft 2 at a point somewhat in front of the socket 11 is a diametric slot 22 match ing similar slots 23 in the wall of the sleeve 7 These slots receive a taper key 2e having the wider end formed with a recess for the reception of a bar or rod 25, which rod has its end threaded and extending through ears 26 formed on opposite sides of the sleeve 7 and there receives nuts 27, the middle portion of the rod engaging the key 24 and holding it in place. Preferably two nuts '27 are applied to each end of the rod 25 so that one nut will lock the other in place against accidental displacement.

The chamber housing the head 14 and adjacent parts will operate as a lubricant reservoir.

Since the center of curvature of the block or ball 12 and of the ring 19, and of the seats for these two members is the same for all, it will be observed that the structure is in the nature of a ball and socket joint connection between the shaft 2 and the rod or shaft 10. Assuming that the rod or shaft 10 and the shaft 2 are in axial alinement, then the reciprocatory movement of the shaft 10 is imparted to the shaft 2 and the head 1 participates in such movement.

7 The shaft'10 and the headla thereof as well as the block or ball 12 and the portion of the shaft 2 engaged thereby are all designed to withstand the heavy shocks due to the impact of the cutter head with the breast of the tunnel. The strain of the return movement of the shaft 2 and cutter head 1 is borne by the head 14, ring 19, and inturned end of the sleeve 7, this strain being slight as compared with the strain due to the sudden stoppage of the cutter head when striking the breast of the tunnel.

Then it is desired to drill the tunnel on a curve or to continue the tunnel at an angle tothe part already drilled, then the shafts 2 and 10 will no longer be in alinement, but are still held in closebonnection without lost motion because of the ball and socket coupling between the shaft 10 and shaft 2. A change in level or curvature of the tunnel will of course be on a long radius or the angle of deflection will be slight.

Therefore the longitudinal axis of the shaft 10 will be but slightly out of alinement with the longitudinal axis of the shaft 2 under any of these circumstances and the structure shown in the drawing is amply strong to resist the strains under which it is placed when the alinement is no longer exact. Even in the ordinary operation of the drilling machine there may be slight changes in alinement between the shafts 10 and 2 andthese changes will be readily compensated for by the ball and socket connection and wear or heating of the parts is avoided by the thorough provision for lubrication. Furthermore the block 12 provides for the turning of the shaft 2 about its longitudinal axis whilethe shaft 10 does not turn, this turning of the shaft 2 being due to the rotative feed of the shaft to turn the cutter head when operating. This rotative movement of the shaft 2 does not drilling side thereof or when it becomes necessary to repair the coupling because of wear or breakage.

'What is claimed is:

1. A universal coupling comprising a member formed at one end with a substantially semi-spherical pocket, a sleeve surrounding the pocketed end of said member and provided with an inwardly directed terminal flange, said flange being provided with a partially spherical seat, a bearing block adapted to the pocket in the said member, a bearing ring adapted to the seat in the flange of the sleeve, and another member extending through the flanged end of the sleeve and at the end within the sleeve provided with a head lodged between the bearing block seated in the end of the first named member and the bearing ring seated in the flanged end of the sleeve.

2. A universal coupling comprising a member provided with a substantially semispherical seat at one end, a substantially semi-spherical block adapted to said seat and formed on one side with a plane face, a headed member having a plane face engaging the plane face of the said block, a bearing ring for the head of the headed member engaging the face thereof remote from the block, said bearing ring having a partly spherical face curved from the same center as the semi-spherical block, and a connecting member carried by the first named member and provided with a partly spherical seat for the bearing ring.

3. A universal coupling comprising a member having a cylindrical head with opposite plane faces, a plano-convex block having the plane face engaging one plane face of the headed member, a member provided with a concave seat for the convex side of the block, a plano-convex bearing ring having the plane face engaging the other nlane face on the headed member, and a sleeve provided with concave seat for the convex side of the bearing ring.

4. A universal coupling comprising a member terminating in a cylindrical head with opposite faces plane and parallel one to the other, a plano convex block having its plane face engaging the outer plane face of the headed member, a member provided with a concave seat for the lano-convex block, a plano-convex bearing ring having the plane face in engagement with the other plane face of the headed member, and a connecting sleeve fast to the member with the concave seat for the block and provided with a tapered end formed with a concaved seat for the ring and housing the cylindrical head of the first named member.

5. A universal coupling comprising two members, a block supported for movement by one of said members, a head carried by the other member, said head being formed with two plane faces one of said faces contacting with said block, a sleeve inclosing the ends of said members, said sleeve being formed with a curved inner wall adjacent one of its ends and a member spacing said head from said curved inner wall, said member having a plane surface contacting with the other plane surface of said head, and a curved surface contacting with said curved wall.

6. A universal coupling comprising two members, a substantially semi-spherical block supported for movement by one of said members, the other member being provided with a head, one face of said head contacting with said block, said contacting face being provided with a spirally arranged groove, a sleeve inclosing the end portions of said members, means for locking said members within said sleeve, and means interposed between the rear face of said head and said sleeve to facilitate the movement of said head.

In testimony that I claim the foregoing as my own, I have hereto aflixed my signature in the presence of two witnesses.

JOHN PRUE KARNS. Witnesses:

ROBERT C. HOERLE, DAN G. PARSONS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

